JPH10306205A - Method for producing polyester resin composition - Google Patents

Abstract

(57) [Abstract] [Problem] A clay compound is uniformly finely dispersed, and mechanical properties,
A polyester resin composition that gives a molded article having a good appearance is obtained. SOLUTION: In producing a polyester resin composition comprising a thermoplastic polyester resin (A) and a clay compound (B), the thermoplastic polyester resin (A) and the clay compound (B) are dispersed in a diol compound (C). The clay compound (B) is dispersed in the thermoplastic polyester resin (A) by melt-mixing the resulting diol dispersion (D) with a kneader, and then a polycondensation reaction is performed to increase the molecular weight. It is characterized by doing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polyester resin composition, and more particularly, to a method for producing a molded article having a clay compound which is finely dispersed uniformly, has excellent mechanical properties and good appearance. It relates to a manufacturing method.

[0002]

2. Description of the Related Art Thermoplastic polyester resins are excellent in heat resistance, chemical resistance, weather resistance, mechanical properties, electrical properties and the like, and are therefore used in many industrial applications as fibers and films. For the purpose of improving the properties of the polyester resin, a method of melt-mixing and blending an inorganic filler such as a layered silicate with an extruder or the like is generally performed. Although the rheological properties and mechanical properties of the polyester resin can be improved by blending the inorganic filler, it is necessary to increase the blending ratio in order to obtain a sufficient improvement effect. However, these inorganic fillers often have a weak affinity for the polyester resin forming the matrix and have no or very weak bonds. Of the surface appearance, increase in specific gravity, and deterioration of the color tone of the product. Further, there are problems such as clogging of a filter and tearing of a film in a process of forming a film or the like. In addition, problems such as fish eyes and appearance such as fish eyes and troubles such as dropout of magnetic tape occur.

[0003] Among the above-mentioned inorganic fillers, the layered silicate has a structure in which about 100 to several thousand unit layers each having a thickness of about 10 ° are laminated. That is, the layered silicate does not exist individually as unit layers, but about one hundred to several thousand unit layers exist as layers. Therefore, even if the layered silicate is uniformly dispersed in the polyester resin, it has heretofore been impossible to disperse the layered silicate in a unit layer state.

The following method is known as an attempt to disperse a layered silicate in a polyester resin in a unit layer state. (1) The above-mentioned finely dispersed material obtained by swelling a layered inorganic filler having a layer charge of 0.2 to 1.0 with glycols and then polymerizing a polyester resin between layers of the layered inorganic filler. Thermoplastic polyester composition comprising a layered inorganic filler and a polyester resin (Japanese Patent Laid-Open No. 7-2
No. 6123), (2) a thermoplastic polyester composition in which an inorganic compound obtained by heat-treating a mixture of talc and an alkali silicofluoride, for example, swellable fluoromica or the like, is dispersed in a thermoplastic polyester. Kaihei 7
-268188, JP-A-8-73710).

However, the present inventors have used swellable fluoromica having a layer charge of 0.6,
Polyethylene terephthalate was melt-polycondensed in the presence of swellable fluorine mica swollen with ethylene glycol to produce a trial composition of polyethylene terephthalate and swellable mica, but the desired dispersion state, layer thickness, and physical properties were obtained. Did not. That is, the elastic modulus and the heat distortion temperature are not improved at all with a small amount of swellable fluoromica, and the layer thickness and dispersion state of the swellable fluoromica in the composition are the same as those of the swellable fluoromica before being blended. It was found by observation with a transmission electron microscope and small-angle X-ray diffraction measurement that this was the case.

On the other hand, it is known that swelling clay such as montmorillonite and swelling mica separates into a unit layer in water and is dispersed in a unit layer size. The interlayer ion of the clay mineral is exchanged with an organic onium ion or the like to be organically converted to a clay complex, thereby dispersing the molecule in a desired organic solvent, melt-mixing with the resin in that state, mixing, etc. It is possible to uniformly and finely disperse the clay compound in a resin at a unit layer level. Therefore, in order to uniformly and finely disperse the clay compound by melt mixing or the like, it is preferable to add the clay compound in a dispersion state in which the clay compound is dispersed in a dispersion medium, rather than in the form of a powder having a laminated structure. It is valid. In accordance with the above concept, for example, Japanese Patent Application Laid-Open No. 2-305
No. 828 discloses a method for producing a polyamide composite material in which the above-mentioned clay composite is swollen with a dispersion medium such as water, ethanol, or lactams and mixed and / or kneaded with a polyamide resin using a kneader. In Japanese Patent Application Laid-Open No. 8-151449, an organic solvent is added at the time of melting and mixing an amorphous thermoplastic resin and a layered silicate, and the vent of a kneading machine is kept at a reduced pressure to reduce the organic solvent. There is disclosed a method for producing an amorphous thermoplastic resin composition which removes phenol.

However, when a layered silicate swollen with a dispersion medium is melt-mixed with a thermoplastic polyester resin in the same manner as described above, the polyester resin is reduced in molecular weight by hydrolysis or the like, and the mechanical properties are reduced. Etc. were significantly reduced and proved to be a problem. As described above, a technique for obtaining a polyester resin composition having excellent physical properties by uniformly and finely dispersing a layered silicate or the like in a thermoplastic polyester resin by melt mixing using a kneader has not yet been provided. is the current situation.

[0008]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a method of dispersing a clay compound such as a layered silicate in a unit layer state in a thermoplastic polyester resin so that even if a small amount of the clay compound is blended, the mechanical properties can be reduced. It is an object of the present invention to provide a method for producing a polyester resin composition which is excellent in the properties and which does not harm the appearance of a molded product even when incorporated in a large amount.

[0009]

Means for Solving the Problems The present inventors have conducted intensive studies to achieve the above object, and as a result, kneaded a thermoplastic polyester resin with a diol dispersion obtained by dispersing a clay compound in a diol compound. Melt-mixing using a mixer to finely disperse the clay compound in the resin, and then perform a polycondensation reaction to increase the molecular weight, achieving the intended purpose, and completed the present invention. did.

That is, in the present invention, when producing a polyester resin composition comprising a thermoplastic polyester resin (A) and a clay compound (B), the thermoplastic polyester resin (A) and the clay compound (B) are diol compounds. The clay compound (B) is dispersed in the thermoplastic polyester resin (A) by melt-mixing the diol dispersion (D) dispersed in (C) with a kneader, followed by a polycondensation reaction. A method for producing a polyester resin composition characterized in that a high molecular weight is obtained by performing the method.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The polyester resin (A) in the present invention is a dicarboxylic acid compound and / or an ester-forming derivative of dicarboxylic acid, and a diol compound and / or
Or a thermoplastic polyester resin comprising an ester-forming derivative of a diol compound. Specific examples thereof include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate, polycyclohexane-1,4-dimethyl terephthalate, and neopentyl terephthalate. , Polyethylene isophthalate, polyethylene naphthalate,
Examples thereof include polybutylene naphthalate and polyhexamethylene naphthalate, and copolymerized polyesters thereof. These are used alone or in combination of two or more.

The aromatic dicarboxylic acids include, for example, terephthalic acid, isophthalic acid, orthophthalic acid,
2,5-naphthalenedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 4,4'-diphenyletherdicarboxylic acid, 4,4'-diphenylmethanedicarboxylic acid,
4,4'-diphenylsulfonedicarboxylic acid, 4,
4'-diphenylisopropylidene dicarboxylic acid and the like, and their substituted products and derivatives can also be preferably used. These may be used alone or in combination of two or more. If the amount is small enough not to impair the properties of the polyester resin (A), one or more aliphatic dicarboxylic acids such as adipic acid, azelaic acid, dodecane diacid, sebacic acid and the like are mixed with these aromatic dicarboxylic acids. it can.

Examples of the diol compound include aliphatic diols such as ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, and neopentyl glycol; alicyclic diols such as 1,4-cyclohexanedimethanol; Aromatic diols such as 4'-dihydroxyphenyl) ethane are exemplified, and their substituted products and derivatives can also be preferably used. These may be used alone or in combination of two or more. Furthermore, if the amount is small enough not to significantly lower the elastic modulus of the polyester resin (A), it is represented by a long-chain diol, for example, an ethylene oxide addition polymer of polyethylene glycol, polytetramethylene glycol, and bisphenol A. One or more kinds of alkylene oxide addition polymers of bisphenols may be mixed.

The molecular weight of the thermoplastic polyester resin (A) is phenol / tetrachloroethane (5/5 weight ratio).
Logarithmic viscosity measured using a mixed solvent is 0.3 to 2.0 dl
/ G is desirable. If the logarithmic viscosity is less than 0.3 dl / g, the resulting molded article of the polyester resin composition has low mechanical properties and impact resistance, and if it is more than 2.0 dl / g, processing such as fluidity during molding. This is not preferable because it causes a problem in the properties.

In the present invention, the diol dispersion (D) melt-mixed with the thermoplastic polyester resin (A) is
It means that the clay compound (B) is dispersed in the diol compound (C).

The clay compound (B) used in the present invention is a group consisting of a layered silicate (α), a clay complex (β), a clay complex intercalation compound (γ), and a clay intercalation compound (δ). It refers to at least one kind selected from the following.

The above-mentioned layered silicate (α) mainly comprises a tetrahedral sheet of silicon oxide and an octahedral sheet of metal hydroxide, for example, swelling of smectite group clay mineral, swelling mica, vermiculite and the like. Clay minerals, kaolin group clay minerals, and the like.

Examples of the smectite group clay mineral include natural or chemically synthesized hectorite, saponite, montmorillonite, stevensite, beidellite, nontronite, bentonite, and the like, and their substituted products, derivatives, and the like. Mixtures are mentioned.

Examples of the swellable mica include natural or chemically synthesized swellable mica such as lithium-type teniolite, sodium-type teniolite, lithium-type tetrasilicon mica, and sodium-type tetrasilicon mica. Or swellable mica having sodium ions, or a substituted or derivative thereof, or a mixture thereof. Vermiculite equivalents, which will be described later, can also be used.

The vermiculite includes a trioctahedral type and a dioctahedral type, and has the following general formula (I)

[0021]

## STR1 ## _{(Mg, Fe, Al) 2} ■ 3 (Si 4-X Al X) O 10 (OH) 2 · (M +, M 2+ 1/2) X · nH 2 O (I)

(Where M is an exchangeable cation of an alkali or alkaline earth metal such as Na and Mg, x = 0.6 to
0.9, n = 3.5 to 5). Natural or synthetic vermiculite is preferably used. In the above general formula (I), when X is less than 0.6 or more than 0.9, dispersion tends to be difficult. When n is less than 3.5, dispersion tends to be difficult, while when n exceeds 5, the handleability of vermiculite itself tends to decrease.

Examples of the kaolin group clay mineral include kaolinite, dickalite, and halloysite, which are naturally or chemically synthesized, or their substitutes, derivatives, or mixtures thereof.

The above-mentioned layered silicate (α) may be used alone or
Used in combination of more than one species. The crystal structure of the layered silicate (α) is desirably high in purity, which is regularly stacked in the c-axis direction. However, a so-called mixed-layer mineral in which the crystal cycle is disordered and a plurality of types of crystal structures are mixed is also used. obtain.

The above-mentioned clay complex (β) is a functional group having a covalent bond and / or a functional group on the surface of the layered silicate (α) in a unit layer state.
Alternatively, it means that the bottom surface interval of the above-mentioned layered silicate (α) is enlarged from the initial value by ionic bonding. The method for producing the clay complex (β) is not particularly limited, and for example, the methods described in JP-A-6-172741 and JP-A-8-65427 can be used. That is, first, a dispersion obtained by dispersing the layered silicate (α) in water or the like to separate the layered silicate into a unit layer state is obtained. Next, an organic onium salt and / or
Alternatively, a surface treating agent is added to introduce at least one kind of functional group on the surface of the silicate (α) in a unit layer state, and then isolated. After isolation, drying is carried out by a usual method, and after drying, pulverization is performed, if necessary, to obtain a clay complex (β).

Here, the organic onium salt is at least one selected from the group consisting of onium ions such as ammonium ion, pyridinium ion, phosphonium ion and sulfonium ion and anions such as halogen ions. Specific examples when the organic onium salt is an ammonium salt include trimethyl dodecyl ammonium chloride, triethyl tetradecyl ammonium chloride, tributyl hexadecyl ammonium chloride, dimethyl didodecyl ammonium chloride, diethyl ditetradecyl ammonium chloride, dibutyl dihexa Decyl ammonium chloride, methyl benzyl didodecyl ammonium chloride, dibenzyl dihexadecyl ammonium chloride, tridecyl methyl ammonium chloride, 12-carboxy dodecyl ammonium chloride, 14-carboxytetradecyl ammonium chloride, 16-carboxy hexadecyl ammonium chloride, the following formula

[0027]

Embedded image

Methyl dodecyl bis (PEG) represented by
Examples thereof include ammonium chloride, p-aminophenylammonium chloride, p-nitrophenylammonium chloride, and ammonium hexanesulfonate. Specific examples of the phosphonium salt include tetrabutylphosphonium chloride, dibutyldidodecylphosphonium chloride, tributyloctadecylphosphonium chloride, dimethyl-12-carboxydodecylphosphonium chloride, and dimethyl-1.
4-carboxytetradecylphosphonium chloride,
Dimethyl-6-aminohexylphosphonium chloride, dimethyl-6-nitrohexylphosphonium chloride and the like can be mentioned. Specific examples in the case of a sulfonium salt include tridodecylsulfonium chloride, didodecyltetradecylsulfonium chloride, methylethylcarboxymethylsulfonium chloride, and the like. Specific examples in the case of a pyridinium salt include 3-nitropyridinium chloride, 3-sulfonic acid pyridinium chloride, 2-phenylpyridinium chloride, 2-aminopyridinium chloride and the like. The above-mentioned organic onium salts may be used alone or in combination of two or more.

The surface treatment agent is at least one selected from the group consisting of a silane coupling agent, a titanate coupling agent, and an alumina coupling agent.

The silane coupling agent preferably has the following general formula (II)

[0031]

Embedded image Y _m SiX _4-m (II)

A silane coupling agent represented by the formula: Here, m is an integer of 0 to 3. Y is preferably each independently a hydrocarbon group having 1 to 25 carbon atoms, a vinyl group, an ester group, an ether group, an epoxy group,
It is a group having at least one functional group selected from the group consisting of an amino group, a carbonyl group, a mercapto group, a halogen, and a hydroxyl group. X is a hydrolyzable group, preferably each independently selected from the group consisting of an alkoxy group, an acyl group, and a halogen. When the carbon number of the hydrocarbon group is larger than 25, the reactivity and handleability of the silane coupling agent tend to decrease.

In the present invention, the hydrocarbon group is a linear or branched (ie, having a side chain) saturated or unsaturated monovalent or polyvalent aliphatic hydrocarbon group, and an aromatic hydrocarbon group.
An alicyclic hydrocarbon group means an alkyl group, an alkenyl group, an alkynyl group, a phenyl group, a naphthyl group, a cycloalkyl group and the like. In the present invention, the alkyl group includes a polyvalent hydrocarbon group such as an alkylene group unless otherwise specified. Similarly, the alkenyl group, alkynyl group, phenyl group, naphthyl group, and cycloalkyl group include alkenylene group, alkynylene group, phenylene group, naphthylene group, cycloalkylene group, and the like, respectively.

In the above general formula (II), Y represents 1 carbon atom.
Examples of the hydrocarbon groups having a lower alkyl group such as decyltrimethoxysilane, those having a lower alkyl group such as methyltrimethoxysilane, 2
Those having an unsaturated hydrocarbon group such as -hexenyltrimethoxysilane, those having a side chain such as 2-ethylhexyltrimethoxysilane, those having a phenyl group such as phenyltriethoxysilane, and 3-β-naphthyl Examples thereof include those having a naphthyl group such as propyltrimethoxysilane, and those having a phenylene group such as p-vinylbenzyltrimethoxysilane. Examples of the case where Y is a group having a vinyl group include vinyltrimethoxysilane, vinyltrichlorosilane, and vinyltriacetoxysilane. Examples of a case where Y is a group having an ester group include γ-methacryloxypropyltrimethoxysilane. Examples of the case where Y is a group having an ether group include γ-polyoxyethylenepropyltrimethoxysilane and 2-ethoxyethyltrimethoxysilane. Examples of a case where Y is a group having an epoxy group include γ-glycidoxypropyltrimethoxysilane. Examples of a case where Y is a group having an amino group include γ-aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, and γ-anilinopropyltrimethoxysilane. Examples of a case where Y is a group having a carbonyl group include γ-ureidopropyltriethoxysilane. Examples of the case where Y is a group having a mercapto group include γ-mercaptopropyltrimethoxysilane. Examples of the case where Y is a group having a halogen include γ-chloropropyltriethoxysilane.

When Y is a group having a hydroxyl group, examples of the coupling agent include N, N-di (2-hydroxyethyl) amino-3-propyltriethoxysilane. The hydroxyl groups may also be in the form of silanol groups (SiOH). Examples of the group having a silanol group include an oligomer of dimethyldihydroxysilane represented by the following formula (III). p is preferably in the range of 2 to 30 from the viewpoint of handleability of the silane treatment agent and reactivity with the swellable silicate.

[0036]

Embedded image

Substitutes or derivatives of the above silane coupling agents may also be used. These silane coupling agents are used alone or in combination of two or more.

Specific examples of titanate-based coupling agents include isopropyltrisisostearoyl titanate, isopropyltris-n-dodecylbenzenesulfonyl titanate, isopropyldimethacryloylisostearoyl titanate, bis (dioctylpyrophosphate) -oxyacetate titanate, bis ( Dioctyl pyrophosphate) -ethylene titanate, dicumylphenyloxyacetate titanate, tetraisopropyl-bis (ditridecyl phosphite) titanate, tetraoctyl-bis (ditridecyl phosphite) titanate, and the like. Substitutes or derivatives of the above titanate-based coupling agents may also be used. These titanate-based coupling agents are:
They may be used alone or in combination of two or more.

Specific examples of the alumina-based coupling agent include the following general formula (IV)

[0040]

Embedded image

(Wherein, R is a hydrocarbon group having 1 to 25 carbon atoms), such as acetoalkoxyaluminum diisopropylate. If the carbon number of R is greater than 25, the handleability of the alumina-based coupling agent tends to decrease. Substitutes or derivatives of these alumina-based coupling agents may also be used. These alumina-based coupling agents are used alone or in combination of two or more.

The above clay composite intercalation compound (γ) is
The above-mentioned clay complex (β) and a compound that facilitates fine dispersion of the clay complex (β) (referred to as a dispersion stabilizer)
And the dispersion stabilizer is sandwiched between the layers of the clay composite (β), whereby the distance between the bottom surfaces is increased. The distance between the bottom surfaces of the clay complex intercalation compound (γ) is enlarged by a factor of at least 2, preferably at least 2.5, more preferably at least 3 times the value of the initial layered silicate.

The dispersion stabilizer, which is a raw material of the above-mentioned clay composite intercalation compound (γ), has no adverse effect on the polyester resin (A), such as decomposition, and at the processing temperature of the polyester resin (A). Is not particularly limited as long as it forms a clay complex intercalation compound (γ) by being sandwiched between layers of the clay complex (β), and various compounds are used. obtain. Specific examples of the dispersion stabilizer include a polyoxyalkylene chain, an amino group, an epoxy group, a carboxyl group, an acid anhydride group, and a polysiloxane such as a linear silicone compound having a phenyl group or the like bonded to the main chain. Compounds having a main chain of a polyether such as polyethylene glycol, polyoxyethylene-polyoxypropylene copolymer, polyether condensate of ethylenediamine and polyoxyethylene glycol oleate, phenol ethoxylate having a substituent and higher alcohol Water-soluble surfactants such as ethoxylates, polymers consisting of structural units containing carbonate bonds, polymers consisting of structural units containing vinyl bonds such as polystyrene, polymethyl methacrylate and polyvinyl acetate, and polyolefin-based polymers such as polyethylene wax. Coalescing, and Li Lin ester compounds and the like.
They may have a substituent. The dispersion stabilizers are used alone or in combination of two or more.

The above-mentioned clay interlayer compound (δ) comprises the above-mentioned layered silicate (α), a compound having polysiloxane as a main chain and / or a compound having polyether as a main chain. Water, a polar solvent that is compatible with water at an arbitrary ratio, and is soluble in a mixed solvent of water and the polar solvent, and the compound is sandwiched between layers of the layered silicate (α); This means that the interval between the bottom surfaces of the layered silicate (α) is larger than the initial value.

Specific examples of the compound having a polysiloxane as a main chain include methylpolysiloxane having a grafted polyoxyethylene chain and methylpolysiloxane having a grafted amino group. Specific examples of the compound having the main chain include water, water and water at an arbitrary ratio in polyethylene glycol, polyoxyethylene-polyoxypropylene copolymer, polyether condensate of ethylenediamine, polyoxyethylene glycol oleate, and the like. Examples thereof include a polar solvent that dissolves and a solvent that is soluble in a mixed solvent of water and the polar solvent. These are used alone or in combination of two or more.

As the diol compound (C) in the diol dispersion (D), one or more of the same diol compounds as those used as monomers for the thermoplastic polyester resin (A) may be used. Can be For example, when the thermoplastic polyester resin (A) constituting the polyester resin composition obtained in the present invention is desired to be a homopolymer, the diol compound used is the same as the diol component of the thermoplastic polyester resin (A). Shall be. Specifically, for example, polyethylene terephthalate (PET) is mentioned as the thermoplastic polyester resin (A) suitably used in the present invention, and the polymer constituting the obtained polyester resin composition is PET alone. Is desired, ethylene glycol is used as the diol compound. Similarly, when polybutylene terephthalate (PBT) is used as the resin and it is desired that the polymer in the obtained resin composition is PBT alone, 1,4-butanediol is used as the diol compound. When it is desired that the thermoplastic polyester resin (A) constituting the polyester resin composition is a copolymer, a diol compound different from the diol component of the thermoplastic polyester resin (A) is used. In this case, if necessary, the aromatic dicarboxylic acid or its ester-forming derivative different from the acid component of the thermoplastic polyester resin (A) is added to the diol dispersion (D) and melt-mixed. can do.

Incidentally, these diol compounds and dicarboxylic acid compounds can be newly added as needed also in the polycondensation reaction described later.

The diol dispersion (D) used in the present invention
In the above, the ash content derived from the clay compound (B) is 1 to 50% by weight, preferably 2 to 40% by weight, and more preferably 3 to 30% by weight. If it is less than 1% by weight,
Since the amount of the diol compound increases, the melt mixing step becomes unstable, which is not preferable. If it exceeds 50% by weight, the dispersibility of the clay compound (B) in the diol dispersion (D) is impaired, and as a result, the dispersibility in the polyester resin composition is impaired, which is not preferable.

The method for preparing the above-mentioned diol dispersion (D) is not particularly limited, and various methods can be used, but efficiency is high when a high-speed stirrer is used. First, the diol compound (C) and the clay compound (B) in an amount corresponding to the solid dispersion concentration that can be sufficiently dispersed in the diol compound (C) are sufficiently mixed using a high-speed stirrer. If the clay compound (B) is not sufficiently dispersed even when directly mixed with the diol compound (C), the following is performed. First, a solvent capable of sufficiently dispersing the clay compound (B) and the clay compound (B)
Are thoroughly mixed to prepare a dispersion. Thereafter, the desired diol compound (C) is added and mixed sufficiently, and then the solvent is removed by a usual fractionation operation or the like. In this case, the solvent is compatible with the diol compound (C) to be added later, and the one having a boiling point lower than that of the diol compound (C) can efficiently prepare the diol dispersion (D). In addition, you may add aromatic dicarboxylic acid or its ester-forming derivative component as needed to the diol dispersion (D) obtained as mentioned above.

In the method for producing a polyester resin composition of the present invention, the ash content derived from the clay compound (B) of the obtained polyester resin composition is 0.1 to 60% by weight, more preferably 0.2 to 50% by weight. % By weight, more preferably 0.1% by weight.
5 to 35% by weight. If it is less than 0.1% by weight, the effect of improving mechanical properties and heat resistance cannot be sufficiently obtained, which is not preferable. If the content exceeds 60% by weight, the surface appearance and workability of the molded product are unfavorably deteriorated.

In the present invention, the kneader used for melt-mixing the thermoplastic polyester resin (A) and the diol dispersion (D) with a kneader is a single-screw extruder, a twin-screw extruder. , A kneader that can apply a high shearing force to the system, such as a Banbury mixer and a roll, and a meshing twin-screw extruder having a kneading disk portion is particularly preferable. The diol dispersion (D) may be added from the resin supply port and melt-mixed with the resin in the solid state, but the clay compound (B) is preferably added to the resin in the molten state and melt-mixed.
Is desirable from the viewpoint of dispersibility and stability of melt mixing. The number of supply ports for the diol dispersion (D) is not particularly limited, and may be adjusted as needed.

In the present invention, the resin in a molten state or the resin solidified by cooling after melt-mixing by a kneader is used.
Superheated, decompressed, put into a reactor that can be stirred, in the case of a resin that has been cooled and solidified, heated again and stirred in a molten state,
The molecular weight is increased by performing a melt polycondensation reaction while removing the diol under reduced pressure. In this case, a diol compound may be added as needed. At this time, as described above, the polyester resin (A) constituting the resin composition
Is desired to be a copolymer, all or part of the diol compound to be added is a diol compound different from the diol component of the thermoplastic polyester resin (A).
If necessary, the above-described aromatic dicarboxylic acid or an ester-forming derivative thereof different from the acid component of the thermoplastic polyester resin (A) can be added.

After melt-mixing as described above, the solid resin obtained by cooling is again melted to carry out a melt polycondensation reaction. Performing the condensation reaction is more efficient and is advantageous in terms of energy saving.

The polymerization catalyst required for the above-mentioned polycondensation reaction is already contained in the starting thermoplastic polyester resin (A). If necessary, metal oxides, carbonates, acetates and alcoholates may be used. And the like can be used by adding one or more of them.

In the present invention, additives such as pigments and dyes, heat stabilizers, antioxidants, ultraviolet absorbers, light stabilizers, lubricants, plasticizers, flame retardants, and antistatic agents may be used according to the purpose. One or two or more can be added.

The polyester resin composition obtained by the present invention can be used for injection molding, hot press molding, and blow molding, and may be obtained by reaction molding in a mold. The molded article thus obtained is excellent in appearance, excellent in mechanical properties and heat resistance, etc., for example, suitably used for automobile parts, household electric parts, household daily necessities, packaging materials, and other general industrial materials. Can be

[0057]

The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the invention thereto.

Examples 1 to 8 Thermoplastic polyester resin (A) The following resins were used. KBK, PBK2
[Polyethylene terephthalate (PET) resin, logarithmic viscosity 0.63] PBT120 manufactured by Kanebo Co., Ltd. [Polybutylene terephthalate (PBT) resin, logarithmic viscosity 0.86]

Clay Compound (B) A natural montmorillonite from Yamagata Prefecture, and synthetic swellable mica and clay composites a and b shown below were used. Clay Complex a 140 g of natural montmorillonite was dispersed in 3.5 liters of pure water using a high-speed stirrer. Thereafter, 14 g of γ- (2-aminoethyl) aminopropyltrimethoxysilane was gradually dropped using a simple pipette, and stirring was continued for 1 hour. The mixture was filtered, dried and pulverized to obtain a clay composite a. Clay complex b Synthetic swellable mica was synthesized according to the method described in JP-A-2-149415. That is, 18.4 parts by weight of a finely pulverized sodium silicofluoride was mixed with 100 parts by weight of talc, and heated at 800 ° C. to obtain a synthetic swellable mica. 200 g of the synthetic swellable mica obtained as described above was dispersed in 3 liters of water, and 103 g of a polyoxyethylene addition type quaternary ammonium salt represented by the following formula was added thereto, followed by stirring at room temperature for 1 hour. Thereafter, the mixture was sufficiently washed with water, filtered by suction, and dried and pulverized to obtain a clay complex b.

[0060]

Embedded image

Diol Compound (C) Ethylene glycol (hereinafter abbreviated as EG) and 1,4-butanediol (hereinafter abbreviated as 1,4-BD) were used.

(1) Preparation of Diol Dispersion (D) The above-mentioned diol compound (C) and clay compound (B) are thoroughly mixed with a high-speed stirrer to give a solid dispersion concentration of 7.5% by weight.
Was prepared.

(2) Production of Polyester Resin Composition At the root of the cylinder, a resin pellet supply port, then a resin melting zone, then a first dispersion supply port, a first kneading disk zone, a first vent port, and then An L / D = 42 same-direction meshing twin-screw extruder equipped with a second dispersion supply port, a second kneading disc zone, and a second vent port was used. The set temperature of the cylinder is 265 ° C. except that the resin pellet supply port is 230 ° C. and the dispersion supply port is 240 ° C. for PET, and the resin pellet supply port is 200 ° C. and dispersion supply for PBT. The temperature was set at 240 ° C. except that the mouth was at 215 ° C. Screw rotation speed is 50rpm
And Using the above twin screw extruder, a total of 2000 g of thermoplastic polyester resin (A) is supplied from the resin pellet supply port.
The above diol dispersion (D) was supplied from the first and second dispersion supply ports at a ratio of clay compound (B) of 6 parts by weight to 100 parts by weight of thermoplastic polyester resin (A) (total 1).
20 g) (80 parts by weight as a dispersion, 1600 g in total) and kneaded to finely disperse the clay compound (B) in the thermoplastic polyester resin (A).

[Molten polycondensation reaction]
Into a liter-scale autoclave, 2,000 g of the resin obtained by the above-described melt mixing and 6.0 g of a hindered phenol-based stabilizer (AO60, manufactured by Asahi Denka Co., Ltd.) were charged. The system was evacuated under a stream of dry nitrogen, and the reaction temperature was about 280 ° C for PET and about 260 for PBT.
A polycondensation reaction was performed in the presence of the finely dispersed clay compound (B) at a temperature of 0 ° C. to increase the molecular weight of the thermoplastic polyester resin to obtain a polyester resin composition.

[Preparation of Test Piece] The polyester resin composition obtained above was pulverized and dried at 130 ° C. for 5 hours. Thereafter, a test piece of 12 × 100 × 6 mm was prepared using a hot press.

[Measurement of Bottom Spacing of Clay Compound (B) by Small Angle X-Ray Diffraction (SAXS)]
And the diol dispersion (D) were subjected to SAXS measurement, and the (001) bottom surface spacing of the clay compound (B) in a dispersed state was calculated from the diffraction peak angle.

[HDT] HDT of the test piece obtained above
Was measured according to ASTM D-648.

[Flexural Modulus] The flexural modulus of the test piece obtained above was measured in accordance with ASTM D-790.

[Measurement of Logarithmic Viscosity] After drying the polyester resin composition in pellet form at 140 ° C. for 4 hours or more, about 100 mg was precisely weighed and phenol / 1,1,2,2-tetrachloroethane = 5 / 20 ml of a 5 (weight ratio) mixed solvent was added and dissolved at 120 ° C. Using an Ubbelohde viscometer, the solution viscosity was measured using an automatic viscosity measuring device (Viscotimer manufactured by Lauda Co.), and the logarithmic viscosity (ηinh) was measured from the following formula (I). The measurement temperature was 25 ° C.

Η inh = {1n (t / t ₀ )} / C (I) where t: value of solution, t ₀ : value of mixed solvent,
C: Concentration (g / dl)｝

Comparative Examples 1 to 8 Using the same extruder as in the examples, PET or PBT 10
6 parts by weight (120 g) of the powdery clay compound (B) was added to 0 parts by weight (2000 g) and melt-mixed to obtain a composite. Evaluation of physical properties was performed in the same manner as in the examples.

Reference Examples 1 and 2 Physical properties of PET or PBT used in Examples and Comparative Examples were evaluated in the same manner as in Examples.

[0073]

[Table 1]

Comparative Examples 9 and 10 1000 g of EG and the clay compound (B) 120 shown in the table
g was sufficiently mixed with a high-speed stirrer to prepare an EG dispersion. In the same autoclave as in the embodiment, the above EG
The dispersion, 2000 g of PET, and 6.0 g of AO60 were charged. At 220 to 260 ° C, PET was depolymerized by transesterification of EG and PET. Then 280
By performing melt polycondensation at a temperature of ° C., a composite comprising the clay compound (B) and PET was obtained. Preparation of test pieces and evaluation of physical properties were performed in the same manner as in the examples.

[0075]

[Table 2]

Example 9 A polyester resin composition was prepared in the following manner using a twin-screw extruder, a heater, a horizontal continuous polymerization reactor having a deaeration port and a stirring blade inside the same as in the above Example. Manufactured. First, a clay complex a was finely dispersed in a resin as a clay compound (B) in the same manner as in Example 3. The obtained resin was added in the molten state from the supply port of the horizontal continuous polymerization reactor and polymerized. In the horizontal continuous polymerization reactor,
The resin which is in a molten state at a temperature of 280 ° C. is decompressed and EG is decompressed while gradually moving from the supply port to the discharge port, so that the polycondensation reaction occurs in the presence of the finely dispersed clay complex a It was made high molecular weight. Preparation of test pieces and evaluation of physical properties were performed in the same manner as in the examples.

[0077]

[Table 3]

[0078]

As described above, according to the present invention, a thermoplastic polyester resin (A) and a diol dispersion (D) obtained by dispersing a clay compound (B) in a diol compound (C).
Are melt-mixed using a kneader, and after finely dispersing the clay compound (B) in the resin, a polycondensation reaction is performed to increase the molecular weight, thereby obtaining mechanical properties such as elastic modulus and heat deformation temperature. The present invention provides a polyester resin composition excellent in various properties such as heat resistance.

Claims (3)

[Claims] When producing a polyester resin composition comprising a thermoplastic polyester resin (A) and a clay compound (B), the thermoplastic polyester resin (A) and the clay compound (B) are converted into a diol compound (C). The clay compound (B) is dispersed in the thermoplastic polyester resin (A) by melt-mixing the dispersed diol dispersion (D) with a kneader, and then subjected to a polycondensation reaction to obtain a high molecular weight. A method for producing a polyester resin composition, comprising: 2. The method according to claim 1, wherein the ash content of the diol dispersion (D) derived from the clay compound (B) is 1 to 50% by weight. 3. The production method according to claim 1, wherein the ash content derived from the clay compound (B) of the polyester resin composition is 0.1 to 60% by weight.